lift, raise
擡 centers on lifting or raising something upward, often with effort or support.
擡 combines 扌 (hand) with 臺, which likely contributes the sound and the idea of a platform or support, suggesting lifting with the hands.
The hand radical 扌 beside 臺, which looks like a raised platform, gives the image of hands lifting something onto a higher level.
For タイ, imagine tying a rope to lift a heavy platform: tie -> タイ, and your hands raise it up.
to raise (one's head)